1. Botany Department, Faculty of Science, Ain Shams University, Abbassia Square-11566, Cairo, Egypt
2. RWS Center for Water Management, Department of Hydrobiology, Zuiderwagenplein 2, 8224 AD Lelystad, The Netherlands
3. Freshwater Biological Association, Far Sawrey Ambleside LA22 0LP, United Kingdom
4. Museo delle Scienze — MUSE, Limnology and Phycology Section, Corso del Lavoro e della Scienza 3, I-38123 Trento, Italy